General Safety A basic understanding of the properties of hydrogen peroxide is the first step in safe handling of this chemical. Decomposition, caused by contamination, liberates oxygen and heat. In dilute solutions the heat evolved is readily absorbed by the water present; in more concentrated solutions the heat raises the temperature of the solution and accelerates the decomposition rate. therefore, all handling procedures must be directed towards maintaining the purity of the product as received. Hydrogen peroxide itself is not flammable, but its decomposition liberates oxygen which supports combustion. Fires caused by hydrogen peroxide are best controlled by using large quantities of water. Hydrogen peroxide is also not considered to be explosive. However, when it is mixed with organic substances, hazardous compounds can result. Small amounts of materials containing catalyst such as silver, lead., copper, chromium, mercury, and iron oxide can cause immediate decomposition and explosive rupture of the containing vessel if the vessel is not properly vented.